1. Field of the Invention
The present invention relates to an image processing apparatus provided with an image memory used by a plurality of control boards performing expanded data processings, a backup processing method, a storage medium storing a program readable by a computer, and a program.
2. Description of the Related Art
Recently MFP (Multi-Function Peripheral) devices, which are equipped with a facsimile function, a printer function, a copier function, have been in demand. There are various kinds of MFP devices, including devices equipped with all available functions, or devices having select functions, but not necessarily all available functions. Many MFP devices which have a control board which is used for processing each function in order to enable a combination of the functions to be simultaneously performed depending on a demand of a user. In addition, an MFP generally requires image memory to perform various image processing and image editing functions (e.g., printing, copying, facsimile).
In most circumstances, when power fails in an MFP before printing facsimile reception image data, if image memory information is erased, it is difficult to revive the erased image data. Therefore, it is preferable for image memory storing the image data which received a facsimile to be backed up. On the other hand, in the printer function or copier function, it is comparatively easy to revive the image data.
In the above-mentioned MFP devices, there are devices in which a printer and copier function come as standard equipment in the device. Also the same device may be optionally equipped with a facsimile function. In such an MFP device, image memory, which is used with printer and copier function, is provided with the device. And if the same image memory is used with the facsimile function in common, an inexpensive MFP device can be provided. And since backing up image memory for image data used in printer and copier functions are not necessary, it is enough to only provide sufficient backup memory for facsimile reception image data. Therefore also, when the digital MFP apparatus does not have a facsimile communication function, there is no need for such a backup.
However, with many MFP apparatuses, an image memory is backed up regardless of whether or not the digital MFP apparatus has a facsimile communication function. For example, Japanese Patent Application Laid-Open No. 8-129511 (corresponding to U.S. Pat. No. 5,719,816) discloses a facsimile apparatus which is provided with an image memory composed of a DRAM etc., and which has a memory reception function. When the facsimile apparatus performs a predetermined memory backup process, the facsimile apparatus determines whether or not effective data is stored in the whole memory so as to avoid waste of a backup battery. While a main power stops, the backup battery is controlled to discharge so as to store information received by refresh processing of the memory.
Specifically, a DRAM (dynamic memory) is used as a storage memory, and the whole storage memory is held (backed up) unconditionally when the main power stops. Only when effective data is stored in the storage memory, the backup function is operated when the main power stops.
However, when the teachings from Japanese Patent Application Laid-Open No. 8-129511 are applied to a configuration in which a facsimile communication function can be provided as an optional feature, a backup process of a memory using a backup battery will be performed regardless of the presence or absence of the facsimile communication function. Therefore, an unnecessary battery for such a backup increases the cost of the apparatus as a whole, thus driving up the cost of the apparatus. Further, there is a drawback in that the backup battery is consumed unnecessarily.
Moreover, in the memory backup method according to Japanese Patent Application Laid-Open No. 8-129511, the backup function is operated according only to the presence or absence of effective data, regardless of the amount of data stored in the storage memory. Therefore, in a case where the storage memory is composed of a plurality of ICs or memory blocks, there is a drawback in that a consumption efficiency of the backup battery is not optimal since the backup function is operated even when the amount of effective data is small.